KR970703207A - METHOD AND DEVICE FOR ROUNDING CANS - Google Patents

Abstract

The invention concerns a rounding device (10) comprising two shaping dies (12, 14) with shaping chambers (22, 24) in order to round a sheet bar (26) about a core (16). The peripheral lengths of the two shaping chambers (22, 24) are each longer than half the can length. During a shaping step, the core (16) penetrates a first shaping chamber (22) by a depth which is greater than the can radius. The sheet bar (26) is thus shaped in the form of a U. In an intermediate shaping stage, an auxiliary core (18) is placed on the core (16) such that, as the second shaping die (14) moves downwards, only the ends of the U-legs of the sheet bar blank (26) are shaped arcuately. When the auxiliary core (18) and part (20) of the first shaping die (12) have been removed, the final can shaping process occurs, in which the second shaping die (14) likewise travels over the centre of the can. The three-stage rounding method enables cans to be rounded highly accurately and carefully.

Description

METHOD AND DEVICE FOR ROUNDING CANS

Since this is an open matter, no full text was included.

1 to 4 are schematic diagrams showing a continuous process of a bending device having a sheet bar to be bent,

Claims (14)

Sheet bar 26 is inserted into the gap between the first forming die 12 comprising one core 16 complementary to the inner contour of the can 27, and the multi-part forming chamber 22. One portion of the forming chamber has an inner contour complementary to the outer contour of the can 27, and the other portion of the chamber raises the height of the forming chamber so that the chamber extends over one half of the can perimeter. The core 16 is relatively inserted into the first molding chamber 22 such that the sheet bar 26 is bent into a substantially U-shaped body, and the core 16 inserted into the first molding chamber 22 is removed from the can. Relatively inserted into the second forming chamber 24 of the second forming die 14, which is complementary to the contour, the two legs of the U shaped body are deformed into cans 27 in the final forming process, in which case the core 16, 18 is inserted into the first forming chamber 22 deeper than the radius of the can, and after the preforming process A method for rounding a can, wherein the core 16, 18 is configured to have a larger cross section during the intermediate molding process, the intermediate molding process being configured such that the spacing of the U-shaped legs of the molding is reduced before the longitudinal molding process. Extends in the direction of the U-shaped leg of the molded body, and the leg of the molded body is inserted into the second molding chamber 24 together with the enlarged cores 16 and 18, thereby contacting the end 26 'of the leg. And the ends 26 'of the legs are curved inwards with respect to the enlarged cores (16,18), respectively, corresponding to the forming chamber contours, without the areas being warped together. 2. The can of claim 1, wherein during the final forming process of the can 27, the cores 16, 18 are inserted into the second forming chamber 24 deeper than the radius of the can so that after the final molding of the can 27, the cans can be removed. And an axis of the inner space of the forming chamber (24) spaced from the front surface (19) of the second forming die (14). Method according to one of the preceding claims, characterized in that the auxiliary core (18) extending from the core (16) complementary to the can is inserted in the axial direction. 4. Method according to claim 3, characterized in that the bending of the two ends (26 ') of the shaped body starts with a slight delay. The process according to any one of claims 1 to 4, wherein the processing of the cans 27 is carried out on two parallel working surfaces, in which at least the preliminary molding process and the final molding process of the cans 27 take place. And then the can is moved to the second working surface in the axial direction and corrected there. The can 27 is moved into the second working surface and onto the expansion bushing 42 of the calibration point after the final forming process by the auxiliary core 18 is completed. Way. The outer contour of the forming chamber according to claim 1, wherein the outer contour of the forming chamber, except for the wall thickness of the can 27, is cross-sectional with the two forming chambers 22, 24 closed during the preforming process. Complementary to the outer contour of the enlarged core (16,18). A pre-molding apparatus for can 27 manufacturing, comprising a lower forming die 12 and an upper forming die 14 for carrying out the method according to any one of the preceding claims. During the process, the core (16, 18) and the first forming chamber each have a larger cross section than during the final forming process. 9. The slide of claim 8, wherein the first forming die 12 supports a slide 20 that can be moved in the axial direction of the can, forming a portion of the first forming chamber 22, and the slide 20 The dividing surface of the first forming die (12) surrounding is laid on the side of the second forming die at a distance from the center of the can. 10. The die 16 according to claim 8 or 9, wherein the core 16 is supplemented by an auxiliary core 17 during the preforming process, with the concave surface overlying the core 16 and the second forming die 14 And a convex working surface complementary to the inner surface of the forming chamber. 11. Bending device according to claim 9 and 10, characterized in that the auxiliary core (28) forms one unit which can be moved together with the slide (20). 12. The mold according to any one of claims 8 to 11, wherein the second forming die 14 consists of two halves 14a, 14b, one half 14b of one half 14b of the driven half 14a. The molding chamber 14 is guided to move in the direction of motion of the forming die and is subjected to an initial stress to the starting position displaced with respect to the other forming die half 14a by spring force, so that the forming chamber 14 is at the edge of the can at the edge of the can. Bending device, characterized in that for forming a step (17) to engage the. 13. The width of the two forming dies 12, 14 is at least equal to twice the width of the can 27, and out of the forming chambers 22, 24 in the axial direction. Each of which includes one calibration chamber 34, 36, the curvature of the two calibration chambers coinciding with the curvature of each forming chamber 22, 24 assigned to the chamber, but each extending only over a circumferential angle of 180 °, And a calibrated cavity having a circumferentially closed circumference corresponding to the outer surface of the can (27) during the final molding process, wherein an expansion device (40, 42) is arranged in the calibrated cavity. 14. The core (16) according to claim 13, wherein the core (16) is hollowed out and penetrates the core with an axially moving actuating rod (38), including one cone (40) in the region of the correction cavity. Bending device, characterized in that it interacts with the inner corner of the buoy (42). ※ Note: The disclosure is based on the initial application.